Certain medical conditions require immediate injection of medication. Conditions requiring such treatment may result from a variety of causes. Among the most serious of those conditions is anaphylaxis (a severe allergic reaction) that, in many cases, can become fatal within minutes if left untreated. Numerous allergens may cause anaphylaxis including insect bites, medications, latex, foods and other various chemical substances. For example, food products having even small quantities of peanuts, seafood or milk products can, in some individuals, induce severe, potentially lethal reactions. In foods, the allergen may be “hidden”, that is, the food unknowingly, may contain a minute trace of an allergenic ingredient or may have been exposed to the allergenic ingredient during its processing. When anaphylaxis occurs, often there is insufficient time for the patient to reach a hospital or other trained and equipped medical personnel.
Individuals known to be at risk for anaphylaxis typically are advised to carry, at all times, an auto-injector apparatus adapted to deliver a dose of Epinephrine. The ability to inject the Epinephrine immediately can be a matter of life or death. Notwithstanding the severe risk involved, there is evidence that a large proportion of the population that should be carrying such an apparatus, in fact, does not. Moreover, even for those individuals that carry such an apparatus, it has been reported that a large proportion are insufficiently familiar with its use and operation.
The most common automatic emergency Epinephrine injector apparatus is the EPIPEN® auto-injector distributed by Mylan, Inc. The EPIPEN® injector is designed to rapidly inject an adult dose of about 0.30 milligrams of Epinephrine. The injector is about six inches long and has an oval tubular shape with a diameter of approximately three inches. The injector is relatively bulky and requires training to be administered correctly since proper use of the device is not intuitive. As a patient may only use the injector infrequently, there may be some confusion in performing the required manipulative steps, particularly when the individual experiencing anaphylaxis may be in a state of panic. Furthermore, should it be necessary for someone other than the patient (e.g., a bystander) to administer the medication, that person may not know how to operate the injector. Additionally, some injectors possess complicated parts requiring multiple hands for proper use and administration. Consequently, precious time may be lost, increasing the risk to the patient. Moreover, confusion has been reported regarding which end of the device the needle protrudes from and, as such, accidental injections into the thumb or finger of the person delivering the medicine are common. Additionally, after the injector has been used to effect an injection, its hypodermic needle often remains exposed, presenting post-injection hazards. Among such hazards are those associated with accidental stabbing or puncture injuries, or the spread of blood born diseases such as HIV and hepatitis B and C.
It would be desirable to provide a more compact, easier to use injector, which patients are more likely to carry on their person, for rapid transcutaneous administration of a predetermined dose of medication. It would also be desirable to provide an injector which can be unlocked, activated, and administered with the use of only one hand.